A prosthetic heart value intended for replacement of a diseased natural aortic valve typically includes a valve body of generally annular configuration, a valve element movably mounted on the valve body for opening and closing the valve, and a suture ring circumscribing the valve body. In the case of a mechanical valve, the valve element may include a ball or a disc. In a leaflet type of valve, the valve element is in the form of valve leaflets.
Implantation of an aortic prosthetic heart valve of this type typically involves, among other things, suturing of the suture ring within the annulus of the aortic valve at the base of the aorta. When placed in this fashion, the valve element lies at the base of the aorta, and the valve body has an annular protrusion which extends through the annulus at the base of the aorta.
One problem created by aortic prostheses of this type is that the projection of the valve body into and through the annulus increases resistance to blood flow and reduces the hemodynamic performance of the valve. In addition, leaflet-type aortic prostheses project from the annulus in a way that disrupts the vortices which develop in the Sinuses of Valsalva. This is undesirable because these vortices assist in closing the valve.